Science fiction fans love to complain about Syfy's mix of wrestling and paranormal reality TV — while obsessively watching shows like Warehouse 13 and Haven. But now at last, there's a chance to get some perspective, by watching a two-hour celebration of Syfy's 20th anniversary. But that's not all this week's TV offers — there are also giant cliffhangers on American Horror Story, Person of Interest, Vampire Diaries and Arrow. And Walter drops acid on Fringe!

Check out tons of details and videos for this week's TV, below.

Today:

Syfy's 20th Anniversary Special (9 PM, Syfy):
It's a star-studded celebration of all things Syfy — hopefully including some glimpses of those totally weird little short vignettes they used to show back in the day during commercial breaks. Here's a list of all the people who are interviewed.

In 1992, one channel set out to push the limits of possibility and imagination on television. Now, 20 years later, we're looking back at two decades of broadcasting the history of ideas with a special retrospective on Syfy's past, a look at the present, and a vision of the future! Tune in to see the evolution of the network, from cult favorites like Mystery Science Theater 3000 and Farscape to breakthrough dramas like Battlestar Galactica and Being Human to original movies that brought us scares from the likes of Sharktopus...and see how Syfy has helped shape a world in which sci-fi, super heroes, horror and fantasy dominate the pop culture landscape!

The past 20 years have been an exploration of the potential for imagination in television. Celebrate it with us, and join us for a look at Syfy's future!

The "look at Syfy's future" could possibly mean some clips from their new show Defiance, or something. Let's hope!

Tuesday:

A Muppets Christmas: Letters to Santa (9 PM, The CW):
Let's hope Uma Thurman is playing her character from Kill Bill. Or maybe the Medusa from the Percy Jackson movie. Anyway, I guess this previously aired on the Disney Channel, but now it's debuting on The CW:

A STAR-STUDDED CHRISTMAS SPECIAL ─ When Gonzo accidentally diverts three letters to Santa, he talks Kermit and his friends into delivering them personally to the North Pole. Guest stars include Nathan Lane, Uma Thurman, Whoopi Goldberg and Jane Krakowski. Kirk R. Thatcher directed the film.

Also on TV tonight: Science is showing three hours of Fringe from 8 to 11. There's a new Dragon Ball GT on Nicktoons at 9 PM. Plus a new Doomsday Preppers on National Geographic at 9 PM, and also a new Mankind: The Story of All of Us on History Channel at 9 PM. And a new episode of Leverage on TNT at 10 PM.

Wednesday:

Arrow (8 PM, The CW):
Yes, even this show is doing a Christmas episode. A dark, gritty Christmas episode. With darkness. And this is the midseason finale.

IT'S CHRISTMAS TIME AT THE QUEEN HOUSEHOLD - Oliver (Stephen Amell) discovers that after he and his father went missing, Moira (Susanna Thompson) and Thea (Willa Holland) stopped celebrating Christmas. Determined to make up for lost time and restore a sense of normalcy to the Queen household, Oliver decides to throw the family a Christmas party. Meanwhile, Tommy (Colin Donnell) asks Laurel (Katie Cassidy) to spend Christmas with him but she points out that Christmas was also her sister Sara's birthday and she needs to be with her father (Paul Blackthorne). Tommy suggests changing things up might be the best way for everyone to heal but Laurel isn't sure her father is ready for that. Meanwhile, Diggle (David Ramsey) tells Oliver someone is murdering the people on his father's list with arrows, which sends Oliver off to face his toughest adversary yet.

The Neighbors (8:30 PM, ABC):
Another midseason finale! And it's a zombie episode, because they already did the Christmas episode.

"Juan of the Dead" - When Hidden Hills' beloved gardener, Juan, unexpectedly dies, the aliens are forced to deal with something totally foreign to them. Debbie and Marty struggle to explain that death is something that comes to all humans, eventually, but Larry Bird is determined to find a way to solve that little problem, starting with the recently departed Juan.

American Horror Story: Asylum (10 PM, FX):
And this show, too, is having a midseason finale. Probably featuring the addition of Zombie Elvis to the cast, the way things are going. (And yes, I know that Elvis wasn't actually dead in 1964. That's the shocking twist.)

The Monsignor takes an unlikely convert under his wing. Lana secures a new piece of evidence that can exonerate Kit. Dr. Arden witnesses a miraculous return.

Also on TV tonight: There's a brand new Dark Matters: Twisted But True at 9 PM on Science. Also at 9: another episode of Dragon Ball GT on Nicktoons.

Thursday:

The Vampire Diaries (8 PM, The CW):
Annnnd... another Christmas episode. I hope Klaus wears a Santa hat while killing his rebellious hybrids.

A WINTER WONDERLAND IN MYSTIC FALLS - As a Winter Wonderland-themed party fills the streets of Mystic Falls, Stefan (Paul Wesley) and Caroline (Candice Accola) find themselves at odds with Tyler (Michael Trevino) over his plans for Klaus (Joseph Morgan) and his hybrids. When Caroline proposes a solution to their problem, Hayley (guest star Phoebe Tonkin) finds a dramatic way to make it clear that she is not on board. Later, Klaus makes a discovery that leads to chaos and violence. Meanwhile, Elena (Nina Dobrev) and Damon retreat to the Gilbert Lake House to help Jeremy (Steven R. McQueen) conquer some dangerous inner demons with the help of Bonnie (Kat Graham) and Professor Shane (guest star David Alpay), who reveals a piece of ancient history that leaves them all speechless.

Last Resort (8 PM, ABC):
Another midseason finale:

"Blue Water" — Sam and James depart the island in a daring rescue attempt. Back on the island of Sainte Marina, a Chinese diplomat arrives to make a deal with Marcus. With scarcity and a prison problem plaguing him, Marcus finds himself treading down a more treacherous path than he could have imagined.

Person of Interest (9 PM, CBS):
And yet another midseason finale. I like how they tell you in advance it ends with a cliffhanger. Just so you know.

THE LATEST POI BECOMES A PERSONAL CRUSADE FOR REESE, WHO IS BEING HUNTED BY THE FBI, ON A CLIFFHANGER EPISODE OF "PERSON OF INTEREST" "Shadow Box" - While the FBI refocuses their efforts to catch "The Man in the Suit," Reese's latest POI becomes a personal quest after he learns that she's the sister of a soldier who was killed in action, on a cliffhanger episode of PERSON OF INTEREST

Beauty and the Beast (9 PM, The CW):
Bucking a trend, this show is doing a wedding episode instead of an Xmas episode. And this, too, is the midseason finale.

WEDDING BELLS RING - When Catherine's (Kristin Kreuk) dad (guest-star Rob Stewart) gets remarried, the bride-to-be and her bridesmaids try to find the daughter-of-the-groom a date for the wedding. Uncomfortable with being set up, Cat reluctantly admits that she's seeing somebody and confides to Vincent (Jay Ryan) that she wishes he could be her date. At the wedding reception, Cat learns about a research grant that Evan (Max Brown) received to study the mutant DNA cells found at local crime scenes. When she tells Vincent about Evan's theory of how the cells are changing to become more animal-like and less human, she encounters an unexpected detour that could change the course of their relationship. Meanwhile, Tess (Nina Lisandrello) and Joe (Brian White) cross the line romantically despite the fact that Joe is a married man.

Also on TV tonight: CBS has the midseason finale of Big Bang Theory at 8 PM, and also the fall finale of Elementary at 10 PM. There's a new Mad on Cartoon Network at 8. Travel has a new Mysteries at the Museum at 9. At 9:30 PM, Nicktoons has the series finale of Dragon Ball GT. USA has a new Burn Notice at 10.

Friday:

Prancer Returns (8 PM, The CW):
You expect some truly bizarre holiday movies from the Hallmark Channel and Lifetime, but now the CW is getting in on the act as well. And this one sounds like a doozy.

A HOLIDAY MOVIE STARRING JOHN CORBETT, MICHAEL O'KEEFE AND JACK PALANCE - A young boy finds a deer in the forest he is sure is Santa's beloved Prancer. Determined to return the creature to the North Pole and his rightful destiny, the child overcomes the cynicism of his family to teach them and us a lesson about the true spirit of Christmas. Joshua Butler directed the film written by Greg Taylor.

Fringe (9 PM, Fox):
Amazingly, this show isn't having a midseason finale — there's also an episode next week. And for once, Walter's not taking a backseat to Peter's drama. It's a good old-fashioned Walter-centric outing. With acid!

In attempt to recall a plan to defeat the Observers, Walter takes an LSD trip down memory lane. Meanwhile, Peter and Olivia trace a mysterious signal to the woods, where they come upon a grisly scene.

Haven (10 PM, Syfy):
Sounds like we're taking a break from the Bolt-Gun Killer case, so we can go back to high school! Here are two somewhat different short synopses we found online:

When a string of bodies leads back to long-buried resentments, the group is unwillingly pulled into a Haven high school reunion... Nathan and Duke go back to their high school to help Audrey apprehend a troubled killer who is wreaking havoc at a student reunion.

Saturday:

Rainbow Dash can't believe her luck when she gets an exclusive invitation to enroll at Wonderbolt Academy, but soon she is wondering whether she is really cut out for the school and whether someone else would be a better fit.

Merry In-Laws (8 PM, Lifetime):Cheers fans, this is your special glimpse of Hell.

In this laugh riot starring Shelley Long and George Wendt, together for the first time since Cheers, as Mr. and Mrs. Claus, who are about to meet their future daughter-in-law, a single, uber-intelligent mother and her equally Mensa-type son. Imagine saying "yes" to your boyfriend's marriage proposal and then finding out that your future in-laws are Mr. and Mrs. Santa Claus!

And now we know what Shelley Long has been up to lately.

The Real St. Nick (10 PM, Lifetime):
That's right, there's more!

Torrey Devitto stars as psychiatrist Kate, who attends to a handsome but unconscious man in a Santa Claus suit who saved her during an earthquake. When he awakens and insists he is Santa Claus, he is placed in the hospital's psychiatric wing, where his Christmas spirit soon "infects" everyone in the ward and Kate can't help falling for the man even before she finds out his real identity.

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Also on TV today: A new Ben 10: Omniverse on Cartoon Network at 9 AM. Plus a new Power Rangers on Nickelodeon at 1 PM. And the season finale of Kaijudo: Rise of the Duel Masters on The Hub at 2 PM. And a new R.L. Stine's The Haunting Hour: The Series on The Hub at 6 PM.

Sunday:

Tron Uprising (Midnight, Disney XD):
Once again, Disney XD is burning off Tron Uprising episodes at midnight Sunday nights. Who will fight for the viewers?

Beck falls into a trap and discovers a shocking secret that will annihilate all of his assumptions about his role as Tron's mentee. While Beck is missing, Able helps uncover a plot to build a super-weapon.

This is followed by a new Motorcity, in which there's a robot rodeo.

Robot Chicken (Midnight, Adult Swim):
It's the Christmas special we thought they were running last week, only to find out it was pushed back a week:

"Robot Chicken's ATM Christmas Special" - The Robot Chicken Christmas Special has Santa nearly missing Christmas; Kano from Mortal Kombat shares the holidays with Mrs. Cage; Justin Bieber's new song is bound to be a Christmas hit; The writers give G.I. Joe a very special Christmas.

Also on TV today: Fox's animated shows are all having their fall finales.